Although the study of the toxicity and risks associated with occupational exposure to nanomaterials is moving forward and numerous meetings have addressed the toxicity and risk of exposure to nanoparticles, no meetings have solely addressed the difficulties in setting occupational exposure limits (OELs) for nanomaterials. The proposed meeting will bring together stakeholders from industry, government agencies, non-government organizations, and academics to focus their talents and expertise on developing strategies for assessing safe workplace exposure levels for nanoparticles. We will hold the meeting at George Washington University (GWU) in Washington, DC. GWU is an academic center of excellence that is nationally renowned for research in occupational health and environmental and occupational health policy issues. There will be co- sponsorship by NYU School of Medicine, ACC, GWU, Ferro Corporation, and the 3M Corporation. The goal of the proposed meeting is to bring together and facilitate discussion among key nanomaterial hygienists, risk assessors, and researchers, and it is anticipated that there will be 75 to 100 attendees. While the meeting will focus on nation-wide efforts to develop OELs for nanomaterials, 2 of the invited speakers, Drs. Pauluhn and Lansiedel, will provide a European perspective on OEL setting. The critical issues have been assigned approximately 1/2 day for presentations and discussions. Full participation of stakeholders, speakers, moderators, and audience is expected and appropriate time for questions, answers, and discussion has been allocated for each session. As a final product of the proposed meeting, a published report will include an overview of the workshop, areas of general consensus and disagreement, and areas needing further research. We anticipate that this report will become a 'state of the science' article with recommendations for the best approaches to developing OELs for diverse nanomaterials with varying degrees of support from toxicity data. PUBLIC HEALTH RELEVANCE: The proposed meeting will bring together stakeholders from industry, government agencies, non- government organizations, and academics to focus their talents and expertise on developing strategies for assessing safe workplace exposure levels for nanoparticles. The meeting will take place in Washington, DC and has a number of co-sponsors. Participation by stakeholders, speakers, and moderators will result in a published report that will provide a 'state of the science' approach (es) to developing safe exposure limits for workplace exposure to nanomaterials. )